激光熔覆铁基Cr_3C_2/MoS_2覆层的组织和摩擦磨损性能  

Microstructure,Friction and Wear Properties of Laser Cladding Fe-based Cr_3C_2/MoS_2 Coatings

作　　者：李爱农[1] 魏成靓 刘娇姣 周文乐 王华君[1] 况诗婷 

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070 [2]广东顺德亿港科技有限公司,广东佛山528318

出　　处：《中国表面工程》2015年第5期77-85,共9页China Surface Engineering

基　　金：国家自然科学基金(51475346);佛山市顺德区经济和科技促进局技术创新专项资金(2012CX040)

摘　　要：采用激光熔覆方法,在45钢表面制备出铁基-Cr3C2/MoS2耐磨减摩覆层,通过OM、SEM、EDS、XRD、摩擦磨损试验及XPS对覆层组织、摩擦磨损性能及磨球表面氧化进行了分析。研究表明,熔覆过程中Cr3C2分解主要生成了Cr23C6硬质相;MoS2部分分解形成了CrS微粒,与保留的MoS2一起对覆层材料起到润滑作用。与铁基合金覆层相比,加入Cr3C2/MoS2颗粒后,覆层的摩擦磨损性能显著改善;加入12Cr3C2/6MoS2后,覆层的摩擦因数降低到0.21,仅为铁基覆层的56%,相对耐磨性为其2倍;与Cr12MoV钢相比,铁基-12Cr3C2/6MoS2覆层的摩擦因数仅为其51%,相对耐磨性为其2.4倍。研究表明,覆层表面磨损形式主要是粘着磨损及磨粒磨损,加入Cr3C2/MoS2颗粒相后覆层的磨损程度减轻。XPS分析表明,其磨球表面形成了Cr、Fe的氧化物,对降低磨耗及摩擦阻力有积极作用。The wear-resisting and antifriction coatings with different proportions of Cr3 C2/MoS2 added in Fe-based al- loy were prepared on 45 steel by laser cladding. Microstructures of the coatings were characterized by optical microscopy （OM）, SEM, EDS and XRD. The friction and wear properties of the coatings were investigated by HT-1000 wear test- er. The oxidation of grinding ball samples were studied by X-ray photoelectron spectroscopy （XPS）. Results show that Cr3C2 iS decomposed and is solidified as Cr23C6 as hard phase during the process of laser cladding. MoS2 is decomposed partially and turned into CrS in coatings, together with the retained MoS2 exhibiting the lubricating effect. Compared with Fe-based alloy coating, the friction and wear properties are significantly improved with the increase of Cr3 C2/MoS2, the friction coefficient of Fe-based 12Cr3 C2/6MoS2 coating decreases to 0.21, being 51% of the pure Fe-based alloy coating, and its rela- tive wear resistance is 2 times of Fe-based alloy. Compared with the Cr12MoV steel, the friction coefficient and relative wear re- sistance of Fe-based 12Cr3 C2/6MoS2 laser coating are 51 % and 2.4 times of Cr12 MoV steel respectively. Results show that ab- rasive wear of the specimens＇ surfaces are the major wear forms, while Fe-based coatings added with Cr3 C2/MoS2 have smaller attrition rate. XPS analysis of grinding ball samples shows that chromium oxide and iron oxide are formed on the surfaces of sam- ples, which has a positive effect on the reduction of wear and friction resistances.

关 键 词：激光熔覆 耐磨相 减摩相 铁基合金 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TG115.58[金属学及工艺—金属学]